Studies on Iranian music are particularly conducted to show its melodic aspects and are highly occupied by the discussions of modal systems of dastgāh-ha and the arrangements and functions of notes and their alteration within a tetrachord and pentachord. In general, we can consider three main factors in melodic contours including directions, intervals and time values. However, accustomed listeners of Iranian music pay little or no attention to microtones and their complicated arrangements. In fact, the combination of those three elements plus the presentation of such features arouse their emotion. In order to study and categorize the melodic shapes of gūsheh-ha of the radīf of Iranian traditional music, a system is designed. In this system, all the main gusheh-ha of seven dstgaāh-ha and five āvāz-ha of the radīf (here the version of Mīrazā Abdullāh is used as the main reference) are studied and the melodic shapes of them are categorized. For each gūsheh two types of melodic movements are recognized, structural and momentary movements. The researcher has used his own experience of familiarity with radīf, as a musician, to distinguish the structural elements from momentary musical incidents. Living in a society is the best way to learn and experience everyday life to make sense of the music and the culture of that society. Nonetheless, in order to categorize the musical elements, a systematic approach, which leads to a sort of comparative examination of data, is working accurately. The approach presented in this study helps to examine the qualitative phenomena of melodic movement in various gūsheh-ha of dastgāh-ha and their subdivisions to acquire a general picture of one of the elements of form in Iranian traditional music. Based on the findings, the central features in melodic shape of gūsheh-ha of the radīf are summarized. In 106 gūsheh-ha of various dastgāh-ha and their subdivisions āvāz-ha which have been studied in this project, pendulum movement of melody and moving level with the very limited tonal material have the highest rank in various melodic shapes and movements. As well as pendulum and level melodic contours as the main melodic movements, there is another movement which is sequential descending of the melody. The findings of this study also revealed that some types of melodic shapes, such as “inverted arc,” “sequential ascending,” and “terrace descending” appears very rarely in melodic movements of Iranian melodies, and ascending melodic movements are not popular in melodic structure of dastgāh-ha. Moreover, melodies in traditional music of Iran are usually tended to move in a level with a very limited tonal material or to have a wave shape outline.